Apparatus for screening and diagnosing by dual stethoscopic and doppler detection

ABSTRACT

The invention concerns an apparatus for early screening of cardiovascular diseases through dual stethoscopic and Doppler detection with means ensuring coherence between the two types of detection. According the invention, the medical screening and diagnosis apparatus comprises a sound transmitting linking conduit ( 3, 33 ) connected, on one end, to a housing ( 100 ) forming at least partly an ear trumpet ( 1 ′) provided with a membrane ( 2 ), and, on the other end, at least an earphone ( 4 ) for listening to a stethoscopic signal from the ear trumpet ( 1 ′). The invention is characterized in that the housing ( 100 ) of the apparatus contains at least an ultrasound probe ( 8 ) designed to enable convergence of reception of the ultrasonic and stethoscopic signals. The probe is connected to a transducer processing circuit ( 37 ) capable of supplying, from a Doppler signal, an audio signal by coupling the processing circuit to a loudspeaker ( 34 ) in contact with the ear trumpet for stethoscopic-type listening, and a video signal by coupling the processing circuit ( 37 ) to display means ( 39 ) to provide visual information.

The invention relates to an apparatus for medical screening anddiagnosis by dual sound detection, of the stethoscopic type, andultrasound detection, of the Doppler type. Such an apparatus permits inparticular a cross diagnosis by coupling of these detections by auditoryand visual analysis. The invention applies to the analysis of arterialpressure, in particular of systolic pressure, and permits, for example,screening of incipient narrowing of the vessels.

Doppler ultrasonography apparatus are presently known which comprise anultrasound probe equipped with means for emitting ultrasound waves andfor receiving these ultrasound waves once they have been reflected by asupport, for example the blood flowing through a vessel in the patient.The slowing or acceleration of this flow is manifested by a positive ornegative variation in the Doppler ultrasound frequency, by addition orsubtraction of a frequency interval of amplitude directly associatedwith the Doppler effect, hereinafter the “Doppler signal”. Themeasurement of the signal or of this variation can provide reliableinformation on the caliber of the section of the vessels explored.

In addition to the ultrasound probe, a Doppler ultrasonography apparatustraditionally comprises successive transducer stages permittingdetection of the Doppler signal (phase shifter, multiplier, amplifierand filter), a phase comparator attributing a positive or negativecharacter to the Doppler interval detected, an audiofrequency amplifier,and a loudspeaker.

However, the examination performed with the aid of such Dopplerapparatus requires specialization, or at least training, in order toacquire and to maintain the practice of interpreting the resultsobtained. It follows, logically, that this examination is left in thehands of specialists, as the general practitioner is not accustomed toperforming this type of examination.

The invention aims to promote Doppler examination so as to permit earlyscreening of cardiovascular diseases, in particular of narrowing of thevessels or incipient arterial disease.

To establish, for example, the presence of incipient arterial disease ofthe legs, it is necessary to test for a difference between the systolicpressure of the legs and arms of the patient. Such a difference isgenerally determined by measuring the systolic pressure index (SPI,being the ratio between the systolic pressures of an arm and leg of thepatient).

Easier screening of arterial disease of the legs will then encourage anoverall evaluation of the arteries, in particular of the coronary andcarotid arteries.

Another object of the invention is to provide for dual detection(stethoscopic and Doppler) guaranteeing a high level of coherencebetween the detections, in order to obtain a diagnosis which is highlyreliable.

To achieve these objects, the invention uses means of integrating theDoppler examination in an apparatus having a stethoscope-type structure,forming part of the range of equipment carried by a generalpractitioner, these means permitting, specifically, convergence of thestethoscopic and Doppler investigations of the same vascular segment(producing a unity of place), with the possibility of providing a dualdetection simultaneously (unity of time).

More precisely, the subject of the invention is an apparatus for medicalscreening and diagnosis by dual detection of stethoscopic and Dopplersignals, comprising a sound-transmitting linking conduit connected, atone end, to a housing which at least partially forms an ear trumpetprovided with a membrane, and, at the other end, to at least oneearpiece for listening to a stethoscopic signal coming from the eartrumpet. In this apparatus, the housing is coupled to at least oneultrasound probe designed to permit convergence of reception of theultrasonic and stethoscopic signals and connected to a transducerprocessing circuit capable of supplying, from a Doppler signal, an audiosignal, by coupling the processing circuit to a loudspeaker in contactwith the ear trumpet for stethoscopic-type listening, and a videosignal, by coupling the processing circuit to viewing means forproviding visual information.

Thus, the invention makes it possible to obtain simultaneous andlocalized convergence of the stethoscopic and Doppler investigationswithout having to move or turn the housing during the examinations.Moreover, the results are communicated with the aid of traditional orstandard means, a stethoscope earpiece or a viewing screen, which allowsfor natural integration of this apparatus in the basic equipmentemployed by a practitioner.

According to preferred characteristics:

-   -   means are provided for delivering and forming a film of        semi-solid product on the skin of the patient, in particular a        gel, for achieving an intimate contact between skin and housing        and for channeling the propagation of the waves; a reservoir of        this product, connected to the delivery means, can be        advantageously accommodated in the housing;    -   the loudspeaker is arranged substantially against the ear        trumpet so that the audio signal is amplified by the ear trumpet        and renders the stethoscopic sound perceptible at the earpiece        via the linking conduit, in the same way as in a stethoscope;    -   a microphone is coupled to the ear trumpet so as to pick up the        stethoscopic sound signal and transmit it, in the form of an        electrical signal, to the processing circuit and produce a video        signal;    -   the viewing means are in the form of a liquid crystal screen        permitting graphic display of a stethoscopic and Doppler signal,        or in the form of light-emitting diodes;    -   a microprocessor is controlled by an interpretation algorithm        and coupled to the processing circuit in order to permit        analysis and a combination of stethoscopic and/or Doppler        measurements, delivered by the processing circuit or else picked        up from stethoscopic listening, and to be able to supply a        stethoscopic diagnosis, Doppler diagnosis and/or cross        diagnosis;    -   a display module with three light-emitting diodes which is        mounted on the housing shows the interpretation and provides a        diagnosis based directly on the measurement of the Doppler        signal or a cross diagnosis based on the interpretation        algorithm by giving preference to the Doppler diagnosis when the        interpretations are divergent, each diode emitting in a specific        color corresponding, respectively, to a positive diagnosis        (existence of a disease), a negative diagnosis (no disease), or        a non-interpretable diagnosis (too much doubt regarding the        measurements) in the case where the stethoscopic signal is not        interpretable, or of malfunction of the apparatus, the diagnosis        then being based on the stethoscopic sound signal;    -   a module for recording and viewing the Doppler or stethoscopic        video signal is provided by wireless connection, for example        radio or infrared, between the electronic processing circuit and        a viewing or printing module;    -   peripheral outputs are provided in order to permit a connection        to a microcomputer or to an audio headset (auxiliary);    -   for simple use of the probe, in particular with the aid of a        finger, an electrical circuit is provided for powering the        ultrasound probe, controlled by an actuator which can be mounted        on the linking conduit or on the housing;    -   the actuator is a multifunction switch which serves also for        selective control to the means for supplying stethoscopic,        Doppler or cross diagnoses by the viewing means, to the means        for triggering the diagnosis on the basis of measurements        delivered by the processing circuit or else picked up from        listening, and to the system for recording and remote viewing;    -   the multifunction is realized by different stages identified by        a decision table or a logic unit for programming the connections        of the circuits as a function of the number of times the        actuator is activated;    -   power supply by cell or by rechargeable battery is also        provided.

According to a first embodiment, the housing forms an ear trumpetaccommodating the ultrasound probe, in particular in a centered manner,and contact means can be interposed temporarily between the ultrasoundprobe and the membrane of the ear trumpet, in order to transmit aDoppler signal to the processing circuit coupled to the loudspeakerwhich emits the audio signal amplified in the ear trumpet.

When the ultrasound probe is not in contact with the membrane, a normalstethoscope is available. But when the probe is placed in indirectcontact with the membrane, an apparatus of the Doppler type isavailable.

The means of interposition preferably comprise an inflatable ballooncovering the distal end of the probe and a device for inflating theballoon. This inflating device can comprise a tubing which brings theballoon into communication with a source of liquid, and means,preferably comprising a button, intended to drive liquid from the sourceinto the tubing, so as to inflate the balloon.

The control actuator and the button intended to drive liquid arepreferably the same button and can be actuated by a finger, and meansare provided which are intended to maintain the flow of liquid when theactuation button is released, which means can in particular be anelectromagnetic coil applying a magnetic holding force to a plunger,made of magnetic material, for driving back liquid.

Moreover, means for delivering semi-solid product can form a filmbetween the skin and the membrane.

Depending on whether or not the balloon is inflated, a Doppler apparatusor a traditional stethoscope is available. It is thus possible, with theaid of the apparatus functioning as stethoscope, to first determineapproximately the anatomical location, for example carotid location,where ultrasonography is to be performed, then carry out the detailedultrasonography operation at this location which has been determined inadvance in an approximate but rapid manner.

It is known that it is desirable, in a Doppler apparatus, to be able totilt the probe. In this first embodiment, means are advantageouslyprovided which are controlled from outside the ear trumpet and areintended to tilt the probe. These means can comprise a cable, preferablya group of four cables at the four cardinal points of the probe, ofwhich one end is fixed to the end of the probe, and means intended topull the other end of the cable. The cable, or a part of the set ofcables, is pulled so as to tilt the end of the probe in order to orientit toward the sound response most perceptible at the earpiece.

According to a second embodiment, the probe is accommodated in thehousing and outside the ear trumpet, the housing forming a substantiallycylindrical turret.

The probe can be inclined by a fixed angle of between about 30 and 70degrees relative to the membrane, preferably between 45 and 55 degrees,in order to optimize the examination by converging the reception of theultrasound signals and that of the stethoscopic signals.

Advantageously, means of prolongation of the probe are provided in orderto compensate for the inclination of the probe. The means for deliveryof the semi-solid product then form a connecting layer between theprolongation of the probe and the patient's skin.

According to a preferred characteristic, the linking conduit isconnected to the bottom of the ear trumpet, farthest from the membrane,and emerges substantially at the center of the upper face of the turret.

Other advantages and characteristics of the invention will becomeevident from reading the following description which relates tonon-limiting illustrative embodiments and is accompanied by appendedfigures, in which:

FIG. 1 is an overall view, partially in cross section, of an example ofthe apparatus according to the invention, in a first embodiment;

FIG. 2 is a cross-sectional view of a part of the linking conduit of theapparatus in FIG. 1, in which an actuator button and the controlcircuits are indicated diagrammatically;

FIG. 3 is a cross-sectional view of the end of this apparatus in theposition of stethoscopic functioning;

FIGS. 4 and 5 are cross sectional views, in accordance with FIG. 3, inthe position of Doppler functioning, in which figures the balloon of theprobe is inflated and the probe emits and receives ultrasound waves, andwhich figures show the engagement and release, respectively, of theactuator button;

FIGS. 6 through 9 show a view, similar to that in FIGS. 4 and 5, inwhich the actuator button tilts, in order to optimize the response ofthe Doppler signal, is then released, and is then actuated again toremove power from all the processing circuits of the apparatus, and isfinally released to return to the position for stethoscopic functioning;

FIGS. 10 a and 10 b show two perspective views, namely an upper one anda lower one, of a housing of the apparatus according to the invention,in a second embodiment;

FIG. 11 shows a cross-sectional view of the housing according to FIGS.10 a and 10 b, in an illustrative embodiment adapted for prioritizedprocessing of the Doppler signal and of the stethoscopic signal in audiomode;

FIG. 12 shows an example of a circuit for processing the Doppler signalsof the apparatus according to the invention;

FIG. 13 shows a cross-sectional view of the housing, in an illustrativeembodiment adapted for prioritized processing of the Doppler signal andof the stethoscopic signal in video mode;

FIG. 14 shows a cross-sectional view of the housing in an alternativeembodiment to the preceding example; and

FIGS. 15 and 16 show two other alternatives for clinical validation of across sectional view of examples of apparatus according to the inventionhaving a stethoscope-type structure.

The apparatus shown in FIG. 1 comprises a stethoscope endpiece E whosehousing 100 is in the form of a conical ear trumpet 1 delimited also bya membrane 2 forming the main base of the ear trumpet, and comprising alinking conduit consisting of a connector 3 and of a flexible tubing 33communicating with two earpieces 4 in the conventional manner of astethoscope S, and on which an electrical source 23 is fixed.

However, in contrast to a conventional stethoscope, and as is shown morespecifically in FIG. 2 and in the overall view of the endpiece in FIG.3, the connector 3 is provided with a hole 5 which has a sealing insertand into which a tubing 6 passes, opening into a balloon 7 which coversthe distal end of an ultrasound probe 8. The tubing 6 is filled withliquid, for example water.

Engaged in the hole 5 there is a cylinder 9 in which a plunger 10 madeof magnetic material slides, which plunger 10 is surrounded by anelectromagnetic coil 11. The plunger 10 is capped by a disk 12 whoseupper face is integral with a rod 13. The rod 13 is mountedtelescopically on the rod 14 of an actuator button 18 by way of tworails 15 which can slide on two other rails 16, themselves integral withthe rod 14, and a spring 17 is interposed between the opposing faces ofthe rods 13 and 14. The actuator button 18 is connected to the upperface of the plunger 10 by a spring 19.

A reservoir of gel 60 is arranged in the cylinder 9, between the plunger10 and the tubing 6. This reservoir is connected to a flexible tube 6 amounted in the tubing 6 then, emerging through sealed orifices in thisand in the connector 3, along the conical wall of the ear trumpet 1. Theend of the tube 6 a is connected to an ejection nozzle 6 b situated incontact with the outer face of the membrane 2. Alternatively, the systemfor distribution of gel and its control means can be mountedindependently of the system for inflating the balloon and its controlmeans.

Four pulleys 20, on which four cables 21 run, are fixed to the cylinder9, and the ends of the cables 21 are fixed at 22 to the probe 8. Theother ends of the cables 21 are fixed to the disk 12.

A cell or a rechargeable battery 23 is mounted on the tubing 33 and isconnected via a line 24 to a recharging socket 25 and to a switch 26.

The button 18 also controls an electronic processing module 27 via apush button 28 located under the control button 18, so that the lattermoves the push button 28 when actuated. The electronic processing modulecomprises the transducer circuits for conversion of the Doppler signalsto audio and video signals.

The electronic processing module 27 is connected to first and secondcircuits, 29 and 30, for electrical connection in particular to amicroprocessor 31 and to an LCD device 32. The first electrical circuit29 supplies the electromagnetic coil 11, and also the microprocessor andthe screen. It powers the probe 8 and a loudspeaker 34 arranged againsta wall of the conical ear trumpet 1. The second electrical circuit 30 isa circuit which controls the recording of the Doppler signal by themicroprocessor 31 and its display on the device 32.

The module 27 has a decision table which is such that a first actuationof the button 28, by pressing the actuator 18, takes us to theconfiguration illustrated in FIG. 4. Having released it, a renewedactuation takes us to the configuration according to FIG. 6. Releasingit again, then actuating it again, takes us to the position in FIG. 8.

The apparatus functions in the following way.

With reference to FIG. 3, in which the balloon 7 is not inflated and theprobe 8 is not powered (thumb 35 not active), the apparatus functions asa stethoscope, supplying a stethoscopic audio signal by propagation ofthe perceptible sound through the membrane 2, the ear trumpet 1 and theflexible conduit 33 to the earpieces 4.

In FIG. 4, the button 18 is activated by the thumb 35 (arrow F1). Thefinger 14 pushes the rod 13, which itself pushes the disk 12 downward,causing the plunger 10 to slide in the cylinder 9. The spring 17 iscompressed.

The liquid contained in the tubing 6 is driven into the balloon 7 whichcomes into contact with the membrane 2. The gel 61 is distributed viathe nozzle 6 b between the membrane 2 and the patient's skin.

At the same time, the button 18 has pushed for the first time on thebutton 28, so that the first electrical circuit 29 is powered. Theelectromagnetic coil 11 is powered and maintains the plunger 10 made ofmagnetic material in place, with the result that the liquid contained inthe tubing 6 continues to be driven and the balloon 7 remains inflated.The microprocessor 31 and the screen 32 are powered.

Using piezoelectric elements, the probe 8, which is also powered, emitsultrasounds De through the membrane 2 and, in return, receives thereflected ultrasounds Dr supplemented by a Doppler frequency interval toform the Doppler signal. The apparatus then functions as a Dopplerultrasonography apparatus. The Doppler signal is converted by theprocessing module 27 in order to supply a sound signal by way of theloudspeaker 34. The sound is then amplified in the ear trumpet,propagated through the linking conduit (connector 3 and tubing 33), thenlistened to at the earpieces 4. It is thus possible to carry out aDoppler examination by stethoscopic listening.

In FIG. 5, the user has stopped pressing the button 18 (arrow F2), butthe plunger 10 has remained in position on account of the fact that thecoil 11 is powered, and the button 28 is returned upward by the spring17.

In FIG. 6, the broken line shows the button 18 tilted by the thumb 35 inorder to optimize the reception of the Doppler signal. This tilting ofthe button 18 also translates into a tilting of the disk 12. The resultof this is that some of the cables 21 are pulled by the disk 12 andcause the end of the probe 8 to tilt. Listening through the earpiece 4,a sound is heard which reaches a maximum at a certain orientation of thebutton 18 and thus of the probe 8. When this orientation is reached, thebutton 18 is pressed again while it maintains its orientation. Itpresses on the button 28, which powers the second circuit 30. TheDoppler signal is recorded by the microprocessor 31 and the result isread on the display screen 32.

The microprocessor can be controlled by software for interpreting theDoppler and stethoscopic results. The stethoscopic results are called upby dedicated keys or by the touch-screen. When the results differ, theDoppler result is preponderant in the interpretation. The finaldiagnosis is displayed in the form of a positive result (disease), anegative result (no anomaly), or a non-interpretable result when thesignals are not sufficiently identified or certain. In the case whereonly the Doppler signal is non-exploitable, the diagnosis is the one(positive or negative) supplied by the stethosocpic signal.

In FIG. 7, the user has stopped pressing the button 18 (arrow F2). Theplunger 10 remains held by the electromagnetic coil 11, so that theballoon 7 remains inflated. The recording continues to be displayed onthe device 32. In FIG. 8, the button 18 is pressed once again (arrowF1), and this presses the button 28. The first and second circuits 29and 30 are thus cut and power is removed from the coil 11.

In FIG. 9, the user has stopped pressing the button 18. The plunger 10,which is no longer held by the coil 11, rises under the effect of thesprings 17 and 19. The liquid contained in the tubing 6 is aspirated.The balloon 7 deflates. The probe 8 has stopped emitting. If so desired,the switch 26 can be pressed in order to disconnect the whole apparatus,so as to save the cell 23.

FIGS. 10 a and 10 b show views of an apparatus housing according to theinvention in a second embodiment. In this second embodiment, the probe 8is accommodated in the housing 100, outside of the bell-shaped eartrumpet 1′.

The housing 100 has a turret shape which is substantially cylindricaland of ovoid cross section. The turret is limited by an upper outletface Fs at the center of which the connector 3 emerges, and by an openlower application face Fi where the flat membrane 2 of the ear trumpetand the end face 8 a of a prolongation 8 b of the inclined probe 8 arepositioned. This prolongation is made of solid or semi-solid materialwhich conducts ultrasound waves, for example silicone gel. In theexample illustrated, it has a cylindrical shape with flat end faces cutat suitable angles.

The end face 8 a of the prolonged probe is covered by a gel 61 in orderto form a continuous connecting layer between the end 8 a and thepatient's skin. An insulating membrane 2′, pierced to keep the end 8 afree, can advantageously close the lower face of the turret in order toavoid penetration of the gel inside the turret.

The gel is controlled by a plunger 36 accessible from the upper face Fs.A switch 38 for powering the probe 8 and a display module 39 are alsoarranged on the housing, the display module being on the upper face Fsin the example illustrated. The switch 38 also serves as a multifunctioncommand, as was described with reference to the first embodiment.

The cross section illustrated in FIG. 11 shows a version which isadapted for priority processing of the signals in audio mode.

The axis Y′Y of the probe is inclined in relation to the central axisX′X of symmetry of the ear trumpet, by a fixed angle of about 50 degreeswith respect to the plane of the membrane 2′. This type of inclinationpermits dual detection by convergence of the Doppler signals andstethoscopic listening downstream of the apparatus, more precisely atthe site of investigation.

In this illustrative embodiment, as in the following ones, the gel 61comes from a reservoir 60 arranged in the housing. The gel is deliveredthrough a flexible tube 6 a via an ejection nozzle 6 b which is situatedin contact with the lower face Fi of the turret. In the case where aninsulating membrane 2′ is used, the nozzle 6 b passes through it via anorifice around which a sealing insert is provided.

The thrust of the plunger 36, mounted telescopically as before, orsimply on a restoring spring, makes it possible to meter the appropriateamount of gel delivered via the nozzle. The reservoir can be refilledvia a flexible tube 62 which connects the reservoir 60 to a refillingorifice 63 integrated in the housing.

In this same example, the probe 8 is connected to a loudspeaker 34mounted on an end face of the ear trumpet 1′ via the transducer circuit37. The Doppler signal is converted by the transducer circuit 37 inorder to supply an audio signal via the loudspeaker 34. As before, thesound is amplified in the ear trumpet, propagated through the linkingconduit 3 and 33, then listened to at the earpieces.

The stethoscopic and Doppler results can be collected and stored, afterevaluation by the operator, in interpretation software. This softwarecontrols the microprocessor of a microcomputer (not shown) connected toan output 101 provided on the housing 100. Alternatively or in additionto this, the Doppler signal, after conversion by the circuit 37, is alsotransmitted to the microcomputer and stored in the form of a videosignal via the output 101. The microcomputer is equipped with a screenwhich shows the graph of the Doppler signal.

The basis of the software is an algorithm which supplies a diagnosisbased on the evaluations of the listening and of the video Dopplersignal. The display module 39 is equipped with three light-emittingdiodes. It is mounted on the upper face Fs of the housing 100 andcoupled to the transducer circuit 37. This module makes it possible toview the interpretation. The interpretation algorithm gives priority tothe Doppler diagnosis when the interpretations are divergent.

The diodes emit in red, orange and green light, respectively:

-   -   the emission of the red diode signifies that the diagnosis is        positive (existence of a disease),    -   the emission of the green diode signifies that the diagnosis is        negative (no disease), and    -   the emission of the orange diode signifies that the result is        not interpretable, because of measurements which are too        “limited”.

An example of a transponder circuit 37 for processing the Dopplersignals is illustrated in FIG. 12. This circuit comprises a modulator 37a for impulsing of the emitted signal D_(e) at 4 MHz, coupled to theprobe 8. The signal received D_(r) by the probe and to be transmitted tothe loudspeaker 34 is processed by the following components in series:

-   -   a low-frequency demodulator 37 b, for example for frequencies        below 8 kHz;    -   an amplifier 37 c, for reaching several tens to several hundreds        of mV; and    -   an audio amplifier 37 d, in voltage and impedance.

The signal is transmitted also to the microprocessor for digitalprocessing 31. This microprocessor controls the supply circuit 24 bycell 23 via the switch 38, and also the viewing of the diagnosis by thediode display module 39 described above.

The diodes are triggered by counting the number of impulse frontsreceived by a Schmidt “trigger” (electronic swivel), making it possibleto overcome parasite impulses. For example, in number of fronts persecond:

-   -   less than 500 fronts: orange diode (insufficient number: result        not interpretable);    -   between 500 and 2000 fronts: green diode triggered;    -   between 4000 and 8000 fronts: red diode triggered;    -   more than 8000 fronts: orange diode (number too high: result not        interpretable).

FIG. 13 illustrates more particularly another version of the secondembodiment, adapted for priority processing of the signals in videomode. In this example, a microphone 40 is placed against the outer wallof the connector 3. Alternatively, it can be arranged in the linkingconduit as long as this position does not cause weakening of theintensity of the direct sound signal, or against the wall of the eartrumpet 1′, or more generally at any suitable location situated on thesound path formed by the ear trumpet.

This microphone is able to pick up the stethoscopic sound signal and isconnected to the transducer circuit 37 in order to transmit it, in theform of an electrical signal, and produce a video signal at the output.Moreover, the Doppler signal received by the probe 8 is also convertedto a video signal.

The video signals are transmitted to a microcomputer, as in thepreceding example (illustrated in FIG. 11) via the output 101, and/or toa viewing and printing module 50 situated at a remote point. To thisend, an antenna 41 is provided to emit the video signals in radio waves.

A signal H is then picked up by the receiver 51 of the viewing module,then processed in a demodulator 52 and in a viewing adapter 53.

Moreover, a headset output 42 is also provided in this example in orderto permit stethoscopic listening based on the sound picked up by themicrophone, or on the Doppler signal converted to an audio signal by thecircuit 37. The audio headset can be in a conventional form withearpieces 4 of the stethoscope type.

As in the preceding example, the video signals (or audio signals aftermanual entering of the interpretation by the operator) are evaluated inthe interpretation software of the microprocessor or viewed on thescreen of the microcomputer.

The display module with three light-emitting diodes 39 permits crossinterpretation based on the Doppler and stethoscopic video signals, theDoppler signal being preponderant in the case of divergence.

The cross section in FIG. 14, which illustrates an alternativeembodiment of the housing from FIGS. 11 and 13, shows the probe 8 in aninclined position relative to the central axis X′X, with an inclinationopposite to that previously described and illustrated. The convergenceof the axis Y′Y of the probe 8 and of the central axis X′X is no longerproduced downstream of the housing, as in the previous example, butupstream of the housing 100, in the area of the flexible tubing 33. Thissolution permits a dual detection which gives priority to the identityof the portion of blood flow, examined successively as a function of itsspeed, compared to the identity of the investigation site.

Advantageously, an electric micromotor 70 controls the inclination α ofa casing 71 into which the probe 8 is slid. The casing and the probe arethen driven in rotation about an axis perpendicular to the central axisX′X in such a way as to adjust the angle of inclination α as a functionof the received signal, in order to optimize the Doppler investigation.

FIGS. 15 and 16 illustrate two other alternative embodiments of clinicalvalidation of the apparatus according to the invention, presenting asimplified structure of stethoscope type.

With reference to FIG. 15, a partition 90 separates the housing 100 intoan upper part 100 a for signal processing, which comprises thetransponder circuit 37, the system of diodes 39 and the switch 38, and alower part 100 b for signal acquisition, in which the microphone 40, theloudspeaker 34, the ear trumpet 1, the supply circuit 24 and the probe 8ensure the same functions as before.

The housing 100 partially accommodates the probe 8, and a sealing ring75 is positioned in the cutout of the housing 100 around the probe 8, inorder to protect and mechanically insulate the probe. Indeed, the ringallows the probe to be fixed to the housing without disturbing thenormal vibrations of the piezoelectric elements of the probe. A Dopplersignal of optimal reception is thus obtained.

In a variant of this example, the lower part 100 b of the housing can beadvantageously curved in its central part in order to promote grippingof the housing of the stethoscope type.

The example in FIG. 16 illustrates a solution even closer to thetraditional stethoscope. In this variant, the housing 100 no longeraccommodates the probe 8 and is reduced to the upper part 100 a forsignal processing (FIG. 15). The probe 8 is fixed along the ear trumpet1 by suitable means known to the person skilled in the art. The systemof diodes is reduced to a single diode 39 a which is able tosuccessively assume the three colors previously described. This diodecan also replace the three-diode system described above in the precedingembodiments.

The invention is not limited to the embodiments described and shown. Forexample, it is possible, in the second embodiment, for themicroprocessor and the viewing module to be arranged as in the firstembodiment, or to provide the viewing module with diodes in each exampledescribed above.

A second probe can also be accommodated in the housing. Each of the twoprobes is then dedicated to a particular zone of the body, for examplethe upper part (arms or neck) and lower part (legs) of the patient. Therespective signals of the probes are set at a dedicated frequency, forexample 4 and 8 MHz. Other probes can also be provided, the ends ofwhich are for example inscribed in a peripheral crown inside or outsideof the ear trumpet. It is then possible to provide an annular envelopein order to form a single annular probe of multiple piezoelectricemitters and receivers.

Moreover, a headset output can also be provided for connecting a headsetcable instead of or in addition to the stethoscopic linking conduit, ineach example. A system for recording and viewing the Doppler orstethoscopic video signal can be is provided in each embodiment, bywireless connection, for example radio or infrared, between theelectronic processing circuit and a viewing or printing module.

The control plunger for the semi-solid product can be accessible fromthe housing, the switch for powering the probe also being arranged atany suitable location situated on the housing.

Moreover, it is possible to transmit the three types of diagnosticinformation by vocal synthesis instead of viewing by diodes. Thesynthetic voice is obtained with the aid of a synthesizer coupled to themicroprocessor and is transmitted through the linking conduit to theearpieces for stethoscopic listening.

It is also possible to provide a system for control (oscillometriccontrol or the like) of the charging of the battery, this system beingcoupled to warning means indicating the need to recharge or replace thebattery or the cell when the charge level is below a certain threshold.Such a system can comprise means for turning off the viewing system orinterpretation means, so as not to deliver erroneous results when thecharge level reaches said threshold.

1. An apparatus for medical screening and diagnosis by dual detection ofstethoscopic and Doppler signals, comprising a sound-transmittinglinking conduit (3, 33) connected, at one end, to a housing (100) whichat least partially forms an ear trumpet (1, 1′) provided with a membrane(2), and, at the other end, to at least one earpiece (4) for listeningto a stethoscopic signal coming from the ear trumpet, wherein thehousing (100) is coupled to at least one ultrasound probe (8) designedto permit convergence of reception of the ultrasonic and stethoscopicsignals and connected to a transducer processing circuit (37) capable ofsupplying, from a Doppler signal, an audio signal, by coupling theprocessing circuit (37) to a loudspeaker (34) for stethoscopic-typelistening, or a video signal or both, by coupling the processing circuit(37) to viewing means (31, 32, 39) for providing visual information. 2.The apparatus for medical screening and diagnosis as claimed in claim 1,in which means are provided for delivering (60, 6 a) and forming (6 b) afilm of semi-solid product (61) on the skin of the patient, forachieving an intimate contact between skin and housing and forchanneling wave propagation.
 3. The apparatus for medical screening anddiagnosis as claimed in claim 1, in which the loudspeaker (34) isarranged substantially against the ear trumpet (1, 1′) so that the audiosignal is amplified by the ear trumpet and renders the stethoscopicsound perceptible at the earpiece (4) via the linking conduit (3, 33),in the same way as in a stethoscope.
 4. The apparatus for medicalscreening and diagnosis as claimed in claim 1, in which a microphone(40) is provided which is coupled to the ear trumpet (1, 1′) to detectthe stethoscopic sound signal and transmit it, in the form of anelectrical signal, to the processing circuit (37) and produce a videosignal.
 5. The apparatus for medical screening and diagnosis as claimedin claim 1, in which the viewing means are in the form of a liquidcrystal screen (32) permitting graphic display of a stethoscopic andDoppler signal, or in the form of a module with light-emitting diodes(39).
 6. The apparatus for medical screening and diagnosis as claimed inclaim 1, which comprises a microprocessor controlled by aninterpretation algorithm and coupled to the processing circuit (37) inorder to permit analysis and a combination of stethoscopic or Dopplermeasurements or both, delivered by the processing circuit (37) ordetected from stethoscopic listening, and to provide stethoscopicdiagnosis, Doppler diagnosis or cross diagnosis or a combinationthereof.
 7. The apparatus for medical screening and diagnosis as claimedin claim 1, which comprises a display module with three light-emittingdiodes (39) which is mounted on the housing (100), which provides aninterpretation and a diagnosis based on the measurement of the Dopplersignal or a cross diagnosis based on the interpretation algorithm bygiving preference to the Doppler diagnosis when the interpretations aredivergent, each diode of the module (39) emitting in a specific colorcorresponding, respectively, to a positive diagnosis, a negativediagnosis, or a non-interpretable result in the case where at least theDoppler measurement is not interpretable.
 8. The apparatus for medicaldiagnosis as claimed in claim 1, wherein, instead of displaying anon-interpretable result when at least the Doppler measurement is such,the diagnosis is in this case based on the measurement of thestethoscopic signal, each diode of the module (39) emitting in thespecific color corresponding, respectively, to a positive diagnosis, anegative diagnosis, or a non-interpretable result, in the case where thestethoscopic signal is not interpretable, or of malfunction of theapparatus, the diagnosis is then based on the stethoscopic sound signal.9. The apparatus for screening and medical screening and diagnosis asclaimed in claim 1, wherein, a system of recording and viewing theDoppler or stethoscopic video signal is provided by wireless connectionbetween the electronic processing circuit (37) and a viewing or printingmodule (50).
 10. The apparatus for medical screening and diagnosis asclaimed in claim 1, wherein in which peripheral outputs (101, 42) areprovided in order to permit a connection to a microcomputer andoptionally to an audio headset.
 11. The apparatus for medical screeningand diagnosis as claimed in claim 1, wherein, for use of the probe withthe aid of a finger (35), an electrical circuit (29) is provided forpowering the ultrasound probe (8), controlled by an actuator (18, 28,38) which can be mounted on the linking conduit (3, 33) or on thehousing (100).
 12. The apparatus for medical screening and diagnosis asclaimed in claim 11, wherein the actuator is a multifunction switchwhich serves also for selective control to the means for supplyingstethoscopic, Doppler or cross diagnoses (29) by the viewing means (31,32, 39), to the means for triggering the diagnosis (30) frommeasurements delivered by the processing circuit (37) or picked up fromlistening, and to the system for recording and remote viewing (50), themultifunction being realized by different stages identified by adecision table or a logic unit for programming the connections of thecircuits as a function of the number of times the actuator (18, 28, 38)is activated.
 13. The apparatus for medical screening and diagnosis asclaimed in claim 1, wherein power supply by cell or by rechargeablebattery (23) is also provided.
 14. The apparatus for medical screeningand diagnosis as claimed in claim 1, wherein the housing (100) forms theear trumpet (1) accommodating the ultrasound probe (8), in a centeredmanner, and contact means (7) are provided to be interposed temporarilybetween the ultrasound probe (8) and the membrane (2) of the ear trumpet(1), in order to transmit a Doppler signal to the processing circuit(37) coupled to the loudspeaker (34) which emits the audio signalamplified in the ear trumpet (1).
 15. The apparatus for medicalscreening and diagnosis as claimed in claim 14, wherein the contactmeans of interposition comprise an inflatable balloon (7) covering thedistal end of the probe (8) and a device (10) for inflating the balloon(7) with liquid.
 16. The apparatus for medical screening and diagnosisas claimed in claim 15, wherein the inflating device comprises a tubing(6) which brings the balloon (7) into communication with a source ofliquid, and means (10) intended to drive liquid from the source into thetubing (6).
 17. The apparatus for medical screening and diagnosis asclaimed in claim 14, wherein the contact means of interposition (7)between the probe (8) and the membrane (2) are controlled from outsidethe ear trumpet (1) by the actuator button (18).
 18. The apparatus formedical screening and diagnosis as claimed in claim 14, wherein meanscontrolled from outside the ear trumpet (1) and intended to tilt theprobe (8) are provided in connection with the actuator button (18). 19.The apparatus for medical screening and diagnosis as claimed in claim14, wherein the means intended to tilt the probe (8) comprise at leastone cable (21), of which one end is fixed to the end of the probe (8),and means (12) intended to pull the other end of the cable (21) and tiltthe end of the probe in order to orient it toward the sound responsemost perceptible at the earpiece.
 20. The apparatus for medicalscreening and diagnosis as claimed in claim 1, wherein a circuit (29) isprovided for powering the ultrasound probe (8) and controlled by theactuator button (18).
 21. The apparatus for medical screening anddiagnosis as claimed in claim 1, wherein a circuit (30) is provided forrecording the Doppler signal and controlled by the actuator button (18).22. The apparatus for medical screening and diagnosis as claimed inclaim 14, wherein the actuator buttons form a single button, and means(11) are provided which are intended to maintain the flow of liquid whenthe actuator button is released, these means comprising a plunger (10)made of a magnetic material for driving the liquid, and anelectromagnetic coil (11) applying a magnetic force for holding theplunger (10).
 23. The apparatus for medical screening and diagnosis asclaimed in claim 1, wherein the probe (8) is accommodated in the housing(100) and outside the ear trumpet (1′), the housing forming asubstantially cylindrical turret.
 24. The apparatus for medicalscreening and diagnosis as claimed in claim 1, wherein the probe (8) isaccommodated partially in the housing (100) and partially outside thehousing, the probe passing through the housing (100) via a sealing ring(75) which mechanically isolates the probe (8).
 25. The apparatus formedical screening and diagnosis as claimed in claim 24, wherein thehousing has a lower part (100 b) curved in its central area.
 26. Theapparatus for medical screening and diagnosis as claimed in claim 1,wherein the probe (8) is outside the housing (100), which is reduced toan upper part (100 a) for signal processing, the probe (8) being fixedalong the ear trumpet (1).
 27. The apparatus for medical screening anddiagnosis as claimed in claim 23, in which the probe (8) is inclinedtoward the central axis (X′X) of the ear trumpet by a fixed angle chosenbetween 30 and 70 degrees relative to the plane of the membrane (2),preferably between 40 and 55 degrees, so as to optimize the examinationby causing convergence of reception of the ultrasound signals and thatof the stethoscopic signals.
 28. The apparatus for medical screening anddiagnosis as claimed in claim 23, in which the housing (100) has aturret shape substantially cylindrical and of ovoid cross section, theturret is limited by an upper face (Fs), at the center of which thelinking conduit (3, 33) emerges, and by an open lower face (Fi) wherethe membrane (2) of the ear trumpet (1′) and the end (8 a) of the probeare positioned.
 29. The apparatus for medical screening and diagnosis asclaimed in claim 23, wherein the probe is prolonged, and means areprovided for delivering (60, 6 a, 6 b) the semi-solid product (61)forming a connecting layer between the end (8 a) of the continuation (8b) of the probe (8) and the skin of the patient.
 30. The apparatus formedical screening and diagnosis as claimed in claim 29, which comprisesa plunger (36) which controls the semi-solid product and is accessiblefrom the housing (100), in particular from the upper face (Fs), theswitch (38) for powering the probe 8 also being arranged on the housing.31. The apparatus for medical screening and diagnosis as claimed inclaim 30, which comprises a reservoir (60) arranged in the housing(100), the gel being delivered through a flexible tube (6 a) via anejection nozzle (6 b) situated in contact with the lower face (Fi) ofthe turret (100), and the thrust of the plunger (36) making it possibleto dose the correct quantity of gel delivered via the nozzle (6 b). 32.The apparatus for medical screening and diagnosis as claimed in claim23, wherein the probe (8) is connected to a loudspeaker (34), mounted onan outer face of the ear trumpet (1′) via the transducer circuit (37),the Doppler signal is converted by the transducer circuit (37) in orderto supply an audio signal via the loudspeaker (34), the sound beingamplified in the ear trumpet, propagated in the linking conduit (3, 33),then listened to at the earpieces (4).
 33. The apparatus for medicalscreening and diagnosis as claimed in claim 32, wherein theinterpretation software which controls the microprocessor of amicrocomputer to be coupled to an output (101) provided on the housing(100) comprises means for retrieving and storing the results ofstethoscopic or Doppler listening or both.
 34. The apparatus for medicalscreening and diagnosis as claimed in claim 33, wherein themicrocomputer is equipped with a screen which shows the graph of theDoppler signal after the Doppler signal has been converted by thecircuit (37) and also transmitted to the microcomputer and stored in theform of a video signal via the output (101).
 35. The apparatus formedical screening and diagnosis as claimed in claim 33, wherein thesoftware provides a diagnosis on the basis of the evaluations which havebeen retrieved and stored, with the aid of the display module with atleast one light-emitting diode (39, 39 a), which is mounted on thehousing (100) and coupled to the transducer circuit (37) for viewing theinterpretation.
 36. The apparatus for medical screening and diagnosis asclaimed in claim 23, wherein the transducer circuit (37) converts intovideo signals the stethoscopic sound signal received by the microphoneas claimed in claim 4 and the Doppler signal received by the probe (8).37. The apparatus for medical screening and diagnosis as claimed inclaim 36, wherein the video signals are transmitted to the microcomputervia the output (101) and/or toward a viewing and printing module (50)situated at a remote point.
 38. The apparatus for screening anddiagnosis as claimed in claim 36, wherein an antenna (41) is provided toemit the video signals picked up by the receiver (51) of the viewingmodule (50), then processed in a demodulator (52) and in a viewingadapter (53).
 39. The apparatus for medical screening and diagnosis asclaimed in claim 36, wherein a headset output (42) is also provided topermit stethoscopic listening based on the sound captured by themicrophone or based on the Doppler signal converted into an audio signalby the circuit (37).
 40. The apparatus for medical screening anddiagnosis as claimed in claim 36, wherein the video signals, and ifappropriate audio signals after pickup, are transmitted to themicroprocessor (100) for evaluation and are viewed on the screen of themicroprocessor.
 41. The apparatus for medical screening and diagnosis asclaimed in claim 36, wherein the display module with light-emittingdiodes (39, 39 a) shows a direct or cross interpretation based on theDoppler and stethoscopic video signals as claimed in claim
 7. 42. Theapparatus for medical screening and diagnosis in claim 36, wherein thedisplay module with light-emitting diodes (39, 39 a) shows a direct orcross interpretation based on the Doppler and stethoscopic video signalsas claimed in claim
 8. 43. The apparatus for medical screening anddiagnosis in claim 2, wherein said means is in a form of a gel.
 44. Amethod of effecting medical screening and diagnosis, which compriseseffecting dual detection of stethoscopic and Doppler signals to effectsaid screening and diagnosis using the apparatus of claim
 1. 45. Themethod of effecting medical severing and diagnosis of claim 44, whereinthe apparatus is applied to screen cardiovascular disease by measuringsystolic pressure to establish a Systolic Pressure Index (SPI).
 46. Themethod of effecting medical severing and diagnosis of claim 45, whereinthe screen cardiovascular disease is an incipient material disease.